import logging
from logging.handlers import RotatingFileHandler
from pathlib import Path

LOG_DIR = Path(__file__).resolve().parent.parent / "logs"
LOG_FILE = LOG_DIR / "app.log"

_FORMAT = "%(asctime)s %(levelname)s [%(name)s] %(message)s"


def setup_logging() -> None:
    """Route all app + uvicorn logging to logs/app.log so errors are traceable
    without depending on however the process happens to be launched."""
    LOG_DIR.mkdir(exist_ok=True)

    handler = RotatingFileHandler(LOG_FILE, maxBytes=10 * 1024 * 1024, backupCount=5)
    handler.setFormatter(logging.Formatter(_FORMAT))

    root = logging.getLogger()
    root.setLevel(logging.INFO)
    root.addHandler(handler)

    # "uvicorn.error"/"uvicorn.access" have propagate=False in uvicorn's default
    # logging config, so they never reach the root handler above and need their
    # own. The parent "uvicorn" logger is deliberately skipped: uvicorn.error
    # already bubbles into it, so attaching there too would double every line.
    for logger_name in ("uvicorn.error", "uvicorn.access"):
        logging.getLogger(logger_name).addHandler(handler)